SEND IT IN! Chris Bosh dunks home two of his 20 points in the Heat’s 109-93 win over the Spurs in Game 4 Thursday night in San Antonio. He also had 13 rebounds. Photo: AP

SEND IT IN! Chris Bosh dunks home two of his 20 points in the Heat’s 109-93 win over the Spurs in Game 4 Thursday night in San Antonio. He also had 13 rebounds.

SAN ANTONIO — When LeBron James and Chris Bosh joined Dwyane Wade in Miami in 2010, they were billed as the Big Three.

But over time, it’s become the Big Two plus Bosh.

While James and Wade are transcendent scorers, as well as players who enjoy the limelight and spotlight that comes with NBA stardom, Bosh carries himself differently. He’s far less visible than his fellow Heat stars, and because of the way Miami has built their roster — fully committing to a small-ball mentality to best-utilize the unique skill set of James — he has had to adjust his game in a variety of ways, including spending a lot more time out near the 3-point line to space the floor offensively and defend much bigger players defensively.

Though Bosh may not have the same profile as his fellow Heat stars, he does provide an invaluable contribution to the way Miami wants to play, as he again proved when he had 20 points and 13 rebounds to help propel Miami to a 109-93 win in Game 4 Thursday night that allowed them to even these Finals at two games apiece heading into Game 5 tomorrow night.

“It takes somebody that’s probably capable of being a lightning rod for a lot of judgment, and unfairly also, because for this to work, we had to put him in situations that are out of the box and would open the door for easy criticism from the outside,” Heat coach Erik Spoelstra said yesterday on a conference call about the unique position he’s put Bosh in. “Everybody wants to put him in a conventional box of being a back-end center and provide that type of postgame for us. But, in reality, he has to do so many other versatile things for us to make this thing work.

“So, he has the mentality to be able to handle that and he has to wear a lot of different hats for us to be successful.”

Bosh, who is battling an ankle injury, also hasn’t ever shied away from being self-critical when he has struggled, as he has through much of these playoffs. Before breaking out in Game 4, Bosh had been averaging under 13 points and shooting under 50 percent in the series, after averaging 11 points and shooting under 40 percent in the conference finals while getting battered by Pacers center Roy Hibbert.

That’s why Bosh’s teammates, at times, have to try and make sure that he doesn’t get too down on himself when things aren’t going well.

“Chris is not a loose guy,” Wade said with a smile. “He’s quiet and to himself. The biggest thing was just trying to let him know how important he is, how important he was going to be to us winning this game tonight. He responded in a good way, but we got to continue to respond if we want to do what we did last year, and that’s win a championship.”

But after the way Bosh played in Game 4 — when, in addition to getting back to knocking down open jumpers, he led a sterling defensive effort that forced the Spurs to miss many point-blank attempts at the rim — he should have plenty of confidence when the series resumes.

“I want to play well every game,” Bosh said. “I want to play to the best of my ability, and sometimes that doesn’t happen. You’re going to have bad games in a long stretch, especially during the playoffs, and that’s when you kind of really have to trust your game and trust what got you here.

“I think before I was really just trying to force some situations, thinking of how I can really get going, and it doesn’t work like that. I just have to really trust my instincts, trust my teammates and just continue to play and let things happen.”